Radiofarmaco per utilizzo diagnostico terapeutico in medicina nucleare e medicina radio guidata

Radiofarmaco per utilizzo diagnostico terapeutico in medicina nucleare e medicina radio guidat

Gold Nanoparticles and Nanorods in Nuclear Medicine: A Mini Review

In the last decade, many innovative nanodrugs have been developed, as well as many nanoradiocompounds that show amazing features in nuclear imaging and/or radiometabolic therapy. Their potential uses offer a wide range of possibilities. It can be possible to develop nondimensional systems of existing radiopharmaceuticals or build engineered systems that combine a nanoparticle with the radiopharmaceutical, a tracer, and a target molecule, and still develop selective nanodetection systems. This review focuses on recent advances regarding the use of gold nanoparticles and nanorods in nuclear medicine. The up-to-date advancements will be shown concerning preparations with special attention on the dimensions and functionalizations that are most used to attain an enhanced performance of gold engineered nanomaterials. Many ideas are offered regarding recent in vitro and in vivo studies. Finally, the recent clinical trials and applications are discussed

Radioguided surgery with β- radiation in pancreatic Neuroendocrine Tumors: a feasibility study

The possibility to use beta(-) decaying isotopes for radioguided surgery (RGS) has been recently proposed, and first promising tests on ex-vivo samples of Meningioma and intestinal Neuroendocrine Tumor (NET) have been published. This paper reports a study of the uptake of Ga-68-DOTATOC in pancreatic NETs (pNET s) in order to assess the feasibility of a new RGS approach using Y-90-DOTATOC. Tumor and healthy pancreas uptakes were estimated from Ga-68-DOTATOC PET/CT scans of 30 patients with pNETs. From the obtained SUVs (Standardised Uptake Value) and TNRs (Tumor Non tumor Ratio), an analysis algorithm relying on a Monte Carlo simulation of the detector has been applied to evaluate the performances of the proposed technique. Almost all considered patients resulted to be compatible with the application of beta(-)-RGS assuming to administer 1.5 MBq/kg of activity of Y-90-DOTATOC 24 h before surgery, and a sampling time of few seconds. In just 2 cases the technique would have required a mildly increased amount of activity or of sampling time. Despite a high physiological uptake of Ga-68-DOTATOC in the healthy pancreas, the proposed RGS technique promises to be effective. This approach allows RGS to find application also in pancreatic diseases, where traditional techniques are not viable

Radiodrug for diagnostic/therapeutic use in nuclear medicine and radio-guided medicine

Radio-drug suitable for performing radio-guided surgery, imaging diagnostics, radio-metabolic therapy

Incidental Finding of an Ovarian Carcinoid on 11C-Methionine PET/CT

A 68-year-old woman with a history of multiple myeloma on regular hematological follow-up and with no previous relevant gynecological diseases was found to have an incidental focal uptake by the right ovary at(11)C-methionine PET/CT (C-MET). Transvaginal ultrasound was then performed showing a 2-cm solid right ovarian mass with irregular borders and moderate vascularization at color Doppler examination. Therefore, the patient underwent bilateral salpingectomy, and the final histological results revealed a rare presentation of mature teratoma with insular carcinoid tumor arising from the right ovary

Mass spectrometry characterization of DOTA-Nimotuzumab conjugate as precursor of an innovative β − tracer suitable in radio-guided surgery

The aim of the present work has been the mass spectrometry characterization of the Nimotuzumab (NIM) antibody chemically modified with the bifunctional chelating agent para-S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraaza cyclododecanetetraacetic acid (p-SCN-Bn-DOTA). The conjugate, upon labeling with the pure β−-emitter 90Y3+ , could represent a promising candidate as radiotracer for an innovative radio-guided surgery (RGS) technique, developed and patented by researchers of our group, which uses a probe system for intraoperative detection of tumor residues exploiting the selective uptake of β−-emitting tracers. The results reported in this study show that multiple DOTA molecules bind to lysine residues of both light and heavy chains of the antibody and, probably, some of them are linked to the variable region of antibody. Moreover, the new mass spectrometric analysis highlights the presence of unreacted NIM in the final product. The information obtained by this work is of fundamental importance in the perspective to utilize this conjugate as a radiocompound after its labeling with 90Y3+ radioisotope. Indeed, the conjugation efficiency and the presence of unreacted NIM affect the specific activity of the final radiotracer which binds specific receptor. © 201

Radioguided surgery with β radiation: a novel application with Ga68

Radio Guided Surgery is a technique helping the surgeon in the resection of tumors: a radiolabeled tracer is administered to the patient before surgery and then the surgeon evaluates the completeness of the resection with a handheld detector sensitive to emitted radiation. Established methods rely on γ emitting tracers coupled with γ detecting probes. The efficacy of this technique is however hindered by the high penetration of γ radiation, limiting its applicability to low background conditions. To overtake such limitations, a novel approach to RGS has been proposed, relying on β− emitting isotopes together with a dedicated β probe. This technique has been proved to be effective in first ex-vivo trials. We discuss in this paper the possibility to extend its application cases to 68Ga, a β+ emitting isotope widely used today in nuclear medicine. To this aim, a retrospective study on 45 prostatic cancer patients was performed, analysing their 68Ga-PSMA PET images to asses if the molecule uptake is enough to apply this technique. Despite the expected variability both in terms of SUV (median 4.1, IQR 3.0–6.1) and TNR (median 9.4, IQR 5.2–14.6), the majority of cases have been found to be compatible with β-RGS with reasonable injected activity and probing time (5 s)

Predicting time to treatment in follicular lymphoma on watchful waiting using baseline metabolic tumour burden

Purpose Asymptomatic patients with follicular lymphoma (FL) and a low tumour burden can be followed without initial therapy, a strategy called watchful waiting (WW). Prediction of the time to treatment (TTT) is still a challenge. We investigated the prognostic value of baseline total metabolic tumour volume (TMTV) and whole-body total lesion glycolysis (WB-TLG) to predict TTT in patients with FL on WW. Methods We conducted a retrospective study of 54 patients with FL (grade 1-3a) diagnosed between June 2013 and December 2019, staged with FDG PET/CT, and managed on WW. Median age was 62 years (range 34-85), stage was advanced (III-IV) in 57%, and FLIPI score was intermediate to high (>= 2) in 52% of the patients. Results The median TMTV and WB-TLG were 7.1 and 43.3, respectively. With a median follow-up of 59 months, 41% of patients started immuno-chemotherapy. The optimal cut-points to identify patients with TTT within 24 months were 14 for TMTV (AUC 0.70; 95% CI 51-88) and 64 for WB-TLG (AUC 0.71; 95% CI 52-89) (p < 0.005). The probability of not having started treatment within 24 months was 87% for TMTV < 14 and 53% for TMTV >= 14 (p < 0.005). TMTV was independent of the FLIPI score for TTT prediction. Patients with both FLIPI >= 2 and TMTV >= 14 had only an 18% probability of not having started treatment at 36 months, while this probability was 75% in patients with TMTV < 14. Conclusion Metabolic tumour volume parameters may add information to clinical scores to better predict TTT and better stratify patients for interventional studies

Feasibility of beta-particle radioguided surgery for a variety of “nuclear medicine” radionuclides

Purpose Beta-particle radioguided tumor resection may potentially overcome the limitations of conventional gamma-ray guided surgery by eliminating, or at least minimizing, the confounding effect of counts contributed by activity in adjacent normal tissues. The current study evaluates the clinical feasibility of this approach for a variety of radionuclides. Nowadays, the only β- radioisotope suited to radioguided surgery is 90Y. Here, we study the β- probe prototype capability to different radionuclides chosen among those used in nuclear medicine. Methods The counting efficiency of our probe prototype was evaluated for sources of electrons and photons of different energies. Such measurements were used to benchmark the Monte Carlo (MC) simulation of the probe behavior, especially the parameters related to the simulation of the optical photon propagation in the scintillation crystal. Then, the MC simulation was used to derive the signal and the background we would measure from a small tumor embedded in the patient body if one of the selected radionuclides is used. Results Based on the criterion of detectability of a 0.1 ml tumor for a counting interval of 1 s and an administered activity of 3 MBq/kg, the current probe yields a detectable signal over a wide range of Standard Uptake Values (SUVs) and tumor-to-non-tumor activity-concentration ratios (TNRs) for 31Si, 32P, 97Zr, and 188Re. Although efficient counting of 83Br, 133I, and 153Sm proved somewhat more problematic, the foregoing criterion can be satisfied for these isotopes as well for sufficiently high SUVs and TNRs. © 2017 Associazione Italiana di Fisica Medic